Apparatus for splitting stone slabs and the like



Nov. 17, 1959 L. H. SCHLOUGH ETAL 2,

APPARATUS FOR SPLITTING STONE SLABS AND THE LIKE Filed Feb. 10, 1958 3 Sheets-Sheet 1 Ill INVENTORS LEON H.'5CHLOU6H WESLEY E-.5cHLouGn BY W: e 6: 7w

ATTOR NE-Y Nov. 17 1959 L. H. SCHLOUGH ET AL 2,

APPARATUS FOR SPLITTING STONE SLABS AND THE LIKE Filed Feb. 10, 1958 3 Sheets-Sheet 2 FIG. 2 Z4 lNvENToRs LEON H. SCHLOUGH WESLEY E .SCHLOUGH "i 382 km ATTORNEY United States Patent APPARATUS FOR srurrmo STONE SLABS AND TH LIKE Leon H. Schlongh, Waite Park, and Wesley E. Schlough,

St. Cloud, Minn.

Application February 10, 1958, Serial N 0. 714,083

7 Claims. (01. 125-23 This invention relates to stone splitting apparatus, and more particularly to a multiple chisel type of stone splitting machine wherein the chisels are firmly engaged with an uneven surface of the stone before splitting pressure is applied thereto.

A number of prior art devices have been developed for the purpose of splitting large slabs of stone where continuous contact across a slab is required in order to effect a controlled split. Where a single straight edge blade is employed, only portions of the blade bear upon an uneven slab and, hence, the remaining areas of the slab may develop transverse cracks when splitting pressure is applied.

In the prior art devices for setting chisels prior to the application of splitting pressure, the sequence of operations requires separate treatment and considerable time is consumed in carrying out each step of the splitting procedure. In some instances, differential pressure is applied as through rocker linkages between pairs of chisels and, in other instances, hydraulic pressure is applied to the rear of the chisels so that self-alignment will take place prior to the application of the splitting pressure. Where rocker devices are employed, it is presumed that each pair of chisels can assume a balanced position which will be equivalent to that of another pair of chisels. This situation, of course, is not true in practice since a pair of chisels differentially coupled may both bear against a high or low area of the slab and, hence, create uneven treatment during splitting of the slab. In the case of the hydraulic adjustment of the individual chisels, line linkages and air pockets will create uneven pressures and it becomes diflicult to subject the individual hydraulic rams required to the pressures utilized in splitting stone slabs and the like.

Another difficulty encountered by prior art devices lies in firmly positioning cutting chisels at both sides of the slab prior to cutting thereof and then repeating the operation where the next slab has a diifrent thickness. The entire bank of upper and lower chisels must be moved to a new position and then brought to firm engagement with the slab before the splitting pressure is applied.

The present invention contemplates eliminating the difficulties encountered by the above mentioned prior art devices and has, as an important object thereof, the provision of apparatus which will quickly and efiiciently split slabs of stone and the like irrespective of the uneven character of one or both of the surfaces thereof.

It is another object of the invention to provide multiple chisel stone splitting apparatus wherein the adjustment of the device for thickness of the slab, setting of the chisels prior to splitting pressure, and the ultimate application of splitting pressure is all automatic and will proceed in orderly fashion after the slab is properly positioned in place in the machine.

A further object of the invention is to provide multiple chisel stone splitting apparatus wherein upper and lower head members are convergently mounted and are capable of resiliently setting wedge members at the rear end of individual chisels so as to solidly position the chisels against the uneven contours of the slab during a period of interruption in the application of hydraulic pressure to the chisels to split the slab.

' posed therebetween.

2,912,970 Patented Nov. 17, 1959 A still further object of the invention is to provide automatically operated apparatus of the class described wherein initial movement of multiple chisels toward a stone slab will continue until one or more chisels engage the slab, whereupon valve mechanism will interrupt the convergent mass movement of the chisels and will divert hydraulic power to setting the individual chisels until they are all in contact with the slab, whereupon increasmg hydraulic pressure on the system will bypass the valve and again apply mass movement to the chisels to effect splitting pressure on the slab.

These and other objects and advantages of our invention will more fully appear from the following description made in connection with the accompanying drawings wherein like reference characters refer to the same or similar parts throughout the several views and in which:

Figure l is a front elevation of our multiple chisel stone. splitting machine, certain hidden portions thereof being indicated in dotted-line representation, and other portions being cut away to better show the construction of the machine;

Figure 2 is a side view taken just inside the left 'guide post of Figure 1, the head assemblies being sectioned somewhat rearwardly to better show the chisel and setting mechanisms disposed therebehind;

Figure 3 is an enlarged View of the head assemblies and chisel setting mechanism similar to the view in Figure 2, but showing the chisel setting mechanism in actuated position;

Figure 4 is an enlarged horizontal section of the valve means taken on the line 4-4 of Figure 1, unessential portions of the hydraulic conduits being omitted from the view;

Figure 5 is a reduced side View of the entire machine, taken from the left in Figure l, certain elements hidden from view being shown in dotted outline; and

Figure 6 is a top fragmentary view of two of the upper wedges showing their relationship to the fixed head and to the wedge bar. 1

With continued reference to the drawings, our stone splitting machine comprises generally a supporting structure 10 having a top head assembly 11 rigidly secured thereto and a movable bottom head assembly 12 adapted to move vertically in the supporting structure 10, as shown in Figure 1. The bottom head assembly is caused to move in its convergent relation with the top head assembly by the hydraulic power ram means 13 mounted at the lower part of the supporting structure 10. Each of the head assemblies 11 and 12 are provided with a multiplicity of upper chisels 14 and lower chisels 15 in confronting relation and lying in the same plane for splitting a slab of stone or the like which may be inter- The chisels 14 and 15 are individually set according to the irregular surface of a slab workpiece automatically in the progress of the conver gence of the heads 11 and 12 under power of the hydraulic power rams 13. The chisel setting mechanism is indicated generally at 16 and is actuated by a chisel setting ram 17 set in motion by closing of valve means 18 in response to pressurized fluid entering under increas ing pressure through the hydraulic pressure line 19. The valve means 18 is automatically actuated by the chisel setting mechanism at the completion of the setting of the chisels to again actuate the hydraulic power rams 13 to continue forcing the bottom head assembly upwardly to complete the splitting of a slab. The general elements set forth above will now be described in greater detail.

Supporting structure 10 comprises a base 20 to which are secured upstanding side plates 21 and heavy guide posts 22 in spaced parallel relation, as shown in Figure 1.

The guide posts are provided with a central slot or spacing 23, as shown in Figure 2. The upper ends of the guide posts 22 are rigidly secured together by the fixed head 11.

The fixed head 11, in turn, comprises a back-up bar 24 having a horizontal blade 25 extending across in the top head assembly 11 and terminating at each side in plates 26 which are firmly secured in the slot 23 by means of nuts and bolts 27 serving to rigidity the supporting structure and the top head assembly 11. Additional strength is achieved through the chisel mount structure 28 which comprises a pair of flanged channels 29, each provided with opposed wedge-receiving slots 36 horizontally aligned across the width of the top head assembly 11.

Disposed within the fixed top head 11 and forming a part of the assembly are a multiplicity of upper chisel members 14, each being independently mounted in sideby-side relation with its chisel edge 31 downwardly directed, as shown in Figures 1 and 2. Each of the chisels 14 is mounted in guided relation between guide pins 32 and guide bars 33 so as to maintain vertical alignment at all times and to permit limited vertical movement within the top head assembly. Each of the chisels 14 is provided with a fiat top 34 and a chisel pin 35 rigidly formed thereon. Bearing against the chisel pin 35 is a leaf spring 36 secured to a bracket 37 secured, in turn, to the chisel mount 28, as shown in Figure 2. The lower beveled edge 38 of the back-up bar 25 opposes the flat heads 34 of each of the upper chisels 14 so as to permit setting of the individual chisels by wedging therebetween as will be subsequently discussed.

The bottom head assembly 12 is intended to reciprocate vertically and, hence, is slldably mounted in the guide posts 22, as shown in Figures 1 and 2. The bottom head assembly has a back-up bar 39 with an upwardly facing beveled surface 40 and provided with side flange areas 41 which are slidably received in the slot 23 formed centrally of the guide posts 22. A chisel mount 42 comprises a pair of channel members 43 which are rigidly secured to the lower back-up bar 39 and bear slidably against the guide posts 22 so as to assist in stabilizing the bottom head assembly. Formed in the chisel mount 42 across the channel members 43 are a multiplicity of wedge-receiving slots 44, the purpose of which will be presently described' A series of lower chisels 15 are mounted in alignment between the channels 43 and are provided at their upper ends with aligned edges 45 and at their lower ends with. hat bearing surfaces 46. Each of the multiplicity of lower chisels 15 are aligned in the same plane with the upper chisels 14 and are permitted vertical movement through a limited distance to adjust for uneven contours in a slab to be split. Guide bars 4-7 are secured to the channels 43 and serve to align the upper ends of chisels 15 while adjustable screws 48 which are threadably mounted in opposed relation in the channels 43 lie in bearing contact with each chisel 15 for aligning the lower end thereof.

Also secured to the channels 43 is the table 49 which has a slot 50 formed transversely thereof for receiving the pointed ends 45 of the lower chisels 15 as shown in Figure 2. The table 49 is braced at each end by brace members 51 which extend downwardly and are secured at their lower ends to a lug 51a which lies in slot 23. Lug 49a extends outwardly from the middle of each side of table 4? and also lies guidedly in slot 23.

Pivotally secured with respect to bottom head 12 at 52 is a double link bar 53 which extends downwardly and is pivoted by pin 54 to a radius bar 55 which is, in turn, secured to the shaft 56. The radius bars 55 operate in unison with the double links 53 as the shaft 56 rotates in bearings 57 mounted in opposed relation at each side of the mounting structure 10.

The bottom head assembly is moved upwardly to cause the lower chisels 15 to converge with the upper chisels 14 by hydraulic power ram means 13. In the form of invention illustrated herewith, the power means 13 comprises a pair of hydraulic rams, each having a base 58 secured to base 20 of the supporting structure 10 and each having an upstanding cylinder 59 within which a ram piston 69 is adapted to reciprocate. The upper ends 61 of the pistons 61; are secured to a plate 62 which, in turn, is secured to the bottom of the chisel mount 42 by means of pins 63. The pins 63 merely position the upper ends 61 of rams 13 with respect to the bottom head assembly 12, but permit limited upwardly directed movement therefrom. Plate 62 is also secured to the chisel mount by means of a bolt and nut as sembly 64, a compression spring 65 surrounding the bolt and urging the plate 62 against the chisel mount 42. When a slab breaks and compression is suddenly released, the spring members 65 permit the bottom head assembly to jump upwardly a short distance, thus relieving stresses on the power rams 13 and other parts of the machine.

In order to prevent the bottom head assembly from descending a greater distance than necessary after each cut, we provide an extensible screw jack 66 which is interposed between the base 29 and the bottom of the bottom head assembly, as shown in Figure 1. The jack member is provided with a sleeve 67 secured to a lug member 63 at the lower end and slidably receiving a beveled gear and screw stop member 69 through the upper end thereof. The beveled gear 69 is rotatably carried by the bottom head assembly 12 which also carries a horizontal crank shaft .70 journaled in bearings 71 secured in turn to the bottom head 12. A crank shaft 70 has a manual crank handle 72 extending outwardly from the machine and a cooperating bevel gear 73 which meshes with the bevel gear 69, as shown. The screw jack 66 thus can be set to limit the lower movement of the entire bottom head assembly 12 as hydraulic pressure is relieved in the rams 63. Tension springs 74 are secured'to lugs 75 on the base 213 and to opposed lugs 76 secured to the underside of the lower head assembly 12. These springs aid in bringing the bottom head assembly 12 to its stopped position against jack 66 and to expel hydraulic fluid from the rams 13 after a out has been made.

An important part of our invention resides in the chisel setting mechanism 16 which is operable to adjust firmly all of the upper and lower chisels 14 and 15 to conform to irregularities in the surface of a slab to be out prior to the actual application of cutting forces. The chisel setting mechanism 16 has interrelated function with respect to both the fixed and moving heads and must be capable of setting the chisels irrespective of the thickness of the slab to be split. On the fixed upper head assembly is provided bracket 77 with an upwardly and outwardly angulated top plate 78 secured thereto for the greater part of the width of the machine. The plate 78 functions as a guide for a multiplicity of wedge members 79 which extend forwardly in guided relation with the slots 39 and in wedging relation with the beveled edge 38 of back-up plate 25 and the flat head 34 of each of the upper chisels 14. As each wedge 79 advances in the slots 30, the corresponding chisels 14 Will be moved downwardly until the chisel edge 31 strikes a slab to be split. The wedge 79 has a slender rod 81 extending rearwardly thereof and parallel to the plate 73 as shown in Figures 6 and 3. Each of the slender rods 31 extends rearwardly through a Wedge bar 81 which lies slidably against the plate 78 and substantially for the total width thereof. The outer ends 82 of rods are threaded and stop nuts 83 which permit the wedges 79 and their rods 80 to slide relatively rearward with respect to the wedge bar 81 but limiting the forward movement thereof. Each of the wedges '79 and its associated rod 80 is provided with a compression spring 84 bearing against the wedge 79 and also against the wedge bar 81. Thus when wedge bar 51 is moved toward the fixed head assembly 11, the

wedge 79 will move therewith until resistance is encountered and then, upon continued movement of the Wedge bar 81, the compression spring 84 will shorten and build up pushing stress against the rear of the wedge 79. I 7

At each end of Wedge bar 81 is a stub shaft 85 to which is pivotally secured an adjustable link 86 having pivotal connection in turn at 87 with a crank arm 88 rigidly secured to shaft 89. Shaft 89 is journaled in bearings 90, in turn secured to the plate 78 by means of bolts 91. A guard 92 may also be secured with respect to the bearings 90 and extend rearwardly to overlie the adjustable link 86 and the wedge bar 81. Both of the crankanns 88 are secured in the same plane with the shaft 89 at opposite ends thereof so that the adjustable links86 are pulled simultaneously to move the wedge bar 81 uniformly toward the chisel mount and to advance each of the wedges 79 in their respective guide slots 30 to apply wedging force against each of the chisels 14. It will be understood, of course, that some of the wedges will be seated or set before others but the associated compression spring 84 will permit continued movement of the wedge bar 81 to its limit position which is shown in the enlarged view of Figure 3.

In a similar manner, the movable bottom head assembly 12 has a bracket adapted to hold a plate 94 in downwardly and outwardly angulated manner substantially across the width of the apparatus as shown in Figures 1 and 3, the bracket means being indicated at 93. The lower chisels -15 each are engaged at their lower flat ends 46 by a wedge 95 which is received in guide slots 44 for the purpose of adjusting the vertical height and setting the chisel edge 45 against the undersurface of a slab to be cut. The wedge 95, of course, is seated also against the beveled edge 40 of the back-up bar 39 so as to firmly hold the chisel 15 in contact with a slab prior to applying splitting pressure. Wedges 95 are appropriately angled to present a flat surface to the rear 46 of each of the chisels 15 and are provided with a thin rod 96 rigidly secured thereto and rearwardly extending in a parallel relation with the plate 94, as in the case of the thin rods 80 of the upper wedges 79. In a similar manner, each of the wedge rods 96 pass through a lower wedge bar 97 and are threaded at their outwardly extending ends 98 to receive stop nuts 99. Also in a similar manner, each of the wedge rods 96 carries a compression spring 100 which bears against the wedge 95 whenever the wedge bar 97 is slidably advanced against the outward end of the compression spring. The wedge rod 97 is provided at each end with axial pins 101 to which is pivoted an adjustable link 102 which in turn is pivoted at'103 to crank bar 104. The crank bar 104is mounted endwise of a shaft 105 and rigidly secured thereto in the same plane so as to provide simultaneous movement of the wedge bar in parallel relation with the bottom head assembly 12. The shaft 105 is journaled in a pair of bearings 106 secured with respect to movable head assembly 12 as opposite sides of the machine. The table 49 is linked by an adjustable rod 107 pivoted to the table at 108 and eccentrically pivoted to shaft 105 so that, when wedge bar 97 is moved inwardly during setting of the wedge members 95, the shaft 105 will be caused to turn in a clockwise direction as viewed in Figure 3 and lower the adjustable rod 107 and the table 49 to leave chisel edge 45 slightly above the supporting surface of the table.

A pair of guard bars 109 are mounted with respect to bearings 106 and may be secured together therewith by means of bolts 110 so as to extend rearwardly and overlie the wedge bar 97.

In order to set all of the chisels 14 and 15 simultaneously and irrespective of the thickness of a slab, the shafts 89 and 105 must operate their crank bars 88 and 104 simultaneously. To this end, we provide a pulley sector 111 which is secured to shaft 89 and in the position shown in Figure 2when the wedges are .released and withdrawn. A cable 112 is secured by clamps 113 to the upper arcuate end of the sector 111 and lies in the circumference of the sector 111, as shown. Cable 112 extends downwardly and passes about an idler pulley 114- which rotates on pin 115 secured in turn to the bottom head assembly as shown in Figures 2 and 3. The cable 112 then extends rearwardly and is trained about a pulley 116 which is rotatably mounted for free rotation on the axial pin 101 and thence the cable 112 extends forwardly about an idler pulley 117 rotatably mounted on pin 118 also secured to the bottom head assembly in spaced relation below the pulley 114. The cable 112 then passes downwardly and is secured by clamp 119 to the supporting structure 10. It will be noted that pulley 116 has a diameter only one half of that of the pulley sector 111 so that upward movement of the pulley sector will cause the same length of travel with its single cable action on the wedge bar 81 as the pulley 116 will cause on its wedge bar 97 through double cable action. it will be further noted that the cable and pulley arrangement is such that the above described action can be obtained irrespective of the position of the bottom head assembly since the cable will merely run about the bottom head assembly pulleys without affecting the position of the wedge bar 97 until the cable 112 is actually shortened by upward movement of the pulley sector 111.

The pulley sector 111 is caused to rise and efiect the resilient setting of the wedges 79 and 95 by means of the chisel setting ram 17 which has a hydraulic cylinder 120 and a piston extension 121 movable upwardly with respect to the base 20 as shown in Figures 1 and 2. The piston extension 121 is pivoted by means of pin 122 to the piston rod 123 which, in turn, extends upwardly and is pivotally secured by bolt 124 to the pulley sector 111 as shown in Figures 2 and 3. Thus upward move ment of the piston rod 123 will cause clockwise movement of pulley sector 111 which, in turn, will raise cable 112 and cause inward simultaneous movement of both the wedge bars 81 and 97. The chisel setting ram is secured to the valve means 18 and lies in constant communication through passageway 125 with the hydraulic pressure line 19 as shown in Figure 4. The piston and extension 121 must, however, overcome the combined forces of all the compression springs 84; and 100 in order to travel upwardly and, when so traveling, is limited by the length of the cylinder 120 so that, in the machine illustrated, a travel of three inches will bring the ram to its stopped position and further pressure will not cause further movement thereof. This stop position thus limits the distance which each of the wedge bars 81 and 97 will travel toward their respective head assemblies.

An important part of our invention concerns the automatic adjustment of the head assemblies and sequential setting of the chisels prior to the splitting of a slab. To this end, we have devised a trip bar assembly which will cause the chisels to be set upon convergent movement of the respective head assemblies at the precise moment that first contact is made between opposed chisels with respect to the slab to be split. A horizontal bar 126 overlies all of the upper wedges 79, as shown in Figure 3. The bar 126 will rise if any one of the wedges '79 is raised upwardly toward the back-up bar 25 prior to striking the beveled edge 38. The bar 126 is mounted on a crank 127 at each end which in turn is pivoted to shaft 128 journaled at each side of the machine with respect to the upper fixed head assembly 11. The crank 127 has a latch member 129 rigidly secured thereto in upstanding relation. Latch member 129, in turn, is provided with a plunger 130 which extends slidably through the latch member and terminates upwardly in a manual handle 131. The plunger 130 is biased downwardly by an internal compression spring 132 and is stopped in its downward movement by collar 133 abutting the latch member 129, as shown in Figure 3. A plunger lifter lug 133a is secured with respect to the pulley segment 111 and is adapted to engage the collar 133 to raise the same whenever the pulley sector 111 is rotated to its upper position shown in Figure 3. A trigger 134 lies transversely in the same plane with the plunger 131i and-has a rearward extension 145 passing through the back-up extension 26 adjacent the side of the apparatus adjacent the wedge setting mechanism 16. The trigger 134 has a compression spring 136 interposed between a shouldered portion 137 and the top back-up plate 26. Extension 135 terminates rearwardly in an adjustable stop 138 which also provides visual indication of the position of the trigger 134. Trigger 134 lies between a pair of guide rollers 139 and 141) which, in turn, are rotatably mounted on the mounting bracket 141. The trigger 134 terminates forwardly in a notch 142, as shown in Figures 2 and 3. The lower end of plunger 13% is adapted to engage the notch 142 and to move the trigger 134 rearwardly. When the trigger is in its forward position, the plunger 131) may either rest upon the top of the trigger 134 or may engage notch 142, depending on the relative positions of latch 129 and trigger 134.

The forward end 143 of the trigger 134 is adapted to abut against a double collar abutment 144 at the side 145 thereof or to lie in contact with the undersurface 146 when the latter is in raised position. The double collar abutment 144 is secured at the upper end of valve extension rod 147 which passes downwardly through the bracket 141 and connects with plunger valve 148 which, in turn, is mounted in the valve means 18 to intercept passageway 149 prior to branching into connected conduits 150 and 151 which supply fluid to the rams 13 previously described. The valve extension rod 147 has an adjustment nut 152 which bears against a compression spring 153 which, in turn, abuts the bracket mount 141, as shown in Figure 3. The entire plunger valve 148, together with its extension 147 and the double collar abutment 144, is thus normally biased downwardly to shut off the passageway 149 but, under high pressures, will be forced upwardly against the compression of spring 153 to permit hydraulic fluid to enter the conduits 150 and 151. In the event it is desired to manually raise the plunger valve 148 in the event of faulty operation, or where the hydraulic pressure is insufficient to raise the valve, we employ a manual re-set handle 154 which is journaled in the back-up plate 26 and terminates outwardly in a hand grip 155, as shown in Figure 3. The other end of the re-set crank terminates in a radius arm 156 to which is pivotally secured a lift rod 157 pivotally secured at its lower end 158 to the valve extension rod 147. Thus, raising the radius arm 155 through twisting of the hand grip 155 will compress the spring 153 and raise plunger 148 to permit hydraulic fluid to readily pass into the power rams 13, as previously described.

The use and operation of our multiple chisel stone splitting machine will be apparent from the foregoing specification and may be summarized as follows.

A stone slab 159 having irregular upper and lower surfaces 160 and 161 respectively is placed upon the table 49 at the proper position with respect to the chisels so that a cut may be made therethrough. Hydraulic pressure is then applied through the pressure line 19 to the valve means 18 with the plunger valve 148 in raised position, that is, with the collar abutment 144 being raised so that the trigger 134 bears against undersurface 146 and retains the extension rod 147 against compression of spring 153. As hydraulic fluid enters the valve means 18, a slight amount of pressure will be applied through passageway 125 to the chisel setting ram 17. However, the compression of the multiplicity of wedge springs 84 and 100 will resist further travel of the chisel setting ram and the low pressure fluid will pass directly into the conduits 150 and 151 to slowly raise the hydraulic power rams 13 and thereby cause the entire bottom head assembly to rise toward the upper top head assembly. Since the table 49 is secured to the bottom head assembly, the slab 159 will rise therewith, the lower chisels 15 having their upper edges 45 substantially flush with the table 49 when in relaxed position. As the bottom head assembly rises, the slab 159 will eventually contact one or more of the upper chisel edges 31 with the upper irregular surface 160. As soon as the highest chisel or chisels 14 raise the trip bar 126 to rock the latch 129 clockwise as shown in Figure 3, then the plunger 130 will retract the trigger 134 and permit the double collar abutment 144 and valve extension rod 147 to snap downwardly and close plunger valve 148. When this condition obtains, no further fluid travel will occur in the conduits 150 and 151 and the upward travel of the bottom head assembly will stop. The increasing pressure applied to the line 19, however, will continue and will soon overcome the resistance of wedge springs 84 and and the chisel setting ram 17 will rotate the pulley sector 111 from the position shown in Figure 2 to that shown in Figure 3. The upper and lower wedges 79 and 95 will thus be moved inwardly to firmly position the cutting edges 31 and 45 respectively against the uneven upper and lower surfaces 160 and 161 of slab 159. With the chisels all firmly set and the chisel setting ram extended its full length in stopped position, the plunger lifter lug 133a will engage collar 133 and retain trip plunger in raised position out of engagement with the notch 142 of the trigger 134. However, since the plunger valve 148 now lies in closed position, the trigger 134 merely snaps forward upon release until the forward edge 143 abuts the side of collar 144. At the same time, table 49 will be lowered by virtue of the turning movement of shaft 105 and the eccentrically pivoted rod 107 so as to create a small clearance between the table and the slab 159 and thereby permit free sus pension of the slab between the chisel edges 31 and 45.

Upon continued increase of the hydraulic line pressure, the chisel setting ram can no longer move and the compression spring 153 is ultimately overcome, thereby raising the plunger valve 148 by virtue of line pressure alone, and, hence, raising the valve extension rod 147 together with the double collar abutment 144. The trigger 134 will then snap forward to underlie the collar 144 and support the surface 146 thereof when the high pressure is ultimately reduced in the valve means 18. With increasing fluid pressure applied through the pressure line 19, the conduits and 151 again receive hydraulic fluid but now under greatly increased pressure. The bottom head assembly now tends to move upwardly with all of the upper and lower chisels 14 and 15 in firm contact with the irregular slab surfaces. Pressure is increased in the power rams 13 until the slab 159 splits in the chisel plane, whereupon pressure in the power rams 13 will immediately become relieved. The application of pressure to the hydraulic line 19 is then interrupted and fluid is permitted to flow reversely therethrough under low pressures or atmospheric pressure. The chisel setting ram will then become lowered under the compression of wedge springs 79 and 100 and the plunger valve 148 will tend to drop under compression of spring 153 when the line pressure is decreased. However, the trigger 134 will have moved forwardly as previously noted, and hence, the plunger valve will remain in its open re-set condition until the next cycle of operations. The plunger lifter lug 133a will become lowered with the pulley sector 111 and the trip bar 126 will lower as the wedges 79 are retracted. The trip plunger 130 will again lie in the notches 142. with the forward end of :the trigger underlying collar abutment 144 in supporting contact with the undersurface 146 thereof. As the hydraulic fluid flows reversely through conduits 150 and 151 from the power rams 13, the entire bottom head assembly will lower. Where a number of consecutive cuts are to be made on slabs of approximately the same thickness, the manual jack 66 may be positioned at a height such as will stop the downward movement of the bottom head assembly with just enough clearance for easy positioning of a new uncut slab.

It may thus be seen that we have devised a versatile stone splitting machine which is positive in splitting accuracy and which is automatic and rapid in each cycle of operations.

It will, of course, be understood that various changes may be made in the form, details, arrangements and proportions of the parts without departing from the scope of our invention as set forth in the appended claims.

What is claimed is:

1. In a splitting machine for stone slabs and the like having uneven surfaces, a supporting structure, a multiplicity of upper chisels having cutting heads downwardly.

disposed in alignment, each being carried by the supporting structure and vertically movable in a common plane, a multiplicity of lower chisels having cutting heads upwardly disposed in alignment and each being carried by the supporting structure and vertically movable in said common plane, hydraulic power means adapted to move all the upper and all the lower chisels convergently with a slab positioned therebetween, a conduit connecting with said hydraulic power means and adapted to supply pressurized hydraulic fluid thereto, valve means in the conduit adapted in closed position to interrupt fiuid flow to said hydraulic power means, trigger mechanism responsive to the chisel first contacting the surface of said slab to close the valve means and interrupt fluid flow to the hydraulic power means, and a hydraulic actuating assembly adapted to set all of said chisels firmly against the slab whereby, upon fluid opening of said valve means, fluid will again be supplied to the hydraulic power means with splitting pressure applied to the evenly set chisels.

2. In a splitting machine for stone slabs and the like having uneven surfaces, a supporting structure, a multiplicity of upper chisels having cutting heads downwardly disposed in alignment, each being carried by the supporting structure and vertically movable in a common plane, a multiplicity of lower chisels having cutting heads upwardly disposed in alignment and each being carried by the supporting structure and vertically movable in said common plane, a hydraulic power ram means adapted to unitarily move all of the upper and all of the lower chisels convergently with a slab positioned therebetween, a conduit connecting With said hydraulic power ram means and adapted to supply pressurized hydraulic fluid thereto, a spring loaded valve in the conduit adapted in closed position to interrupt fluid flow to said hydraulic power ram means, trigger mechanism responsive to movement of the chisel which first contacts the surface of said slab to release the spring loaded valve to closed position, a hydraulic actuating assembly adapted to set all of said chisels firmly against the opposed surfaces of said slab, and a hydraulic pressure pump for applying hydraulic fluid at increasing line pressure to the valve and to the hydraulic actuating assembly, said spring loaded valve subsequent to setting of said chisels yielding under increasing fluid pressure to permit bypassing of hydraulic fluid to said power ram means and thereby subject the slab to uniform splitting pressure.

3. A machine for splitting stone slabs and the like having irregular surfaces which comprises, a supporting structure, a fixed head secured to said supporting structure and carrying a multiplicity of chisels mounted in side-by-side relationship and each longitudinally slidable in a plane for a limited distance, a movable head mounted on the supporting structure and carrying a multiplicity of chisels in side-by-side relationship and each longitudinally slidable in said plane for a limited distance in convergence with the respective chisels of the fixed head,

a hydraulic power means adapted to convergently move the movable head with respect to the fixed head and with a slab to be split positioned therebetween, a multiplicity of wedge members mounted laterally -,of said plane in both the fixed head and the movable head, one each for advancing a chisel convergently toward its opposed chisel, a mechanism for resiliently urging all the wedges against the rearward ends of their respective chisels so as to slide the chisels and firmly set the forward ends thereof against the opposed surfaces of said slab, a valve controlling said hydraulic power means, and trigger means linked to said valve and actuable by at least one of said chisels when first contacting the surface of the slab whereby to interrupt the converging splitting movement of the movable and fixed heads until said wedges and said chisels have all become set against the irregular surfaces of the slab.

4. The mechanism set forth in claim 3, and trigger reset means actuable by said wedge actuating mechanism v whereby to latch the trigger means and valve in open position upon the resumption of increased fluid pressure to the hydraulic power means.

5. The mechanism set forth in claim 3, and a visible indicator movable in response to said trigger to indicate complete movement of said wedge actuating mechanism.

6. In a splitting machine for stone slabs and the like having irregular surfaces, a supporting structure, a multiplicity of upper chisels having cutting heads downwardly disposed in alignment, each being carried by the supporting structure and vertically movable in a common plane, a multiplicity of lower chisels having cutting heads upwardly disposed in alignment and each being carried by the supporting structure and vertically movable in said common plane, hydraulic power means adapted to move all the upper and all the lower chisels convergentlywith a slab positioned therebetween, a conduit connecting with said hydraulic power means and adapted to supply pressurized hydraulic fluid thereto, valve means in the conduit adapted in closed position to interrupt application of fluid power to the chisels and to automatically set all the chisel cutting heads firmly against the slab and then to open and permit fluid pressure to applied evenly to the chisels and to the slab along a predetermined line, and trigger mechanism responsive to the chisel first contacting the surface of said slab to close said valve means and to automatically set all the chisel cutting heads against the slab prior to applying additional cutting pressure thereon.

7. In a splitting machine for stone slabs and the like having irregular surfaces, a supporting structure, a multiplicity of upper chisels having cutting heads downwardly disposed in alignment, each being carried by the supporting structure and vertically movable in a common plane, a multiplicity of lower chisels having cutting heads upwardly disposed in alignment and each being carried by the supporting structure and vertically movable in said common plane, hydraulic power means adapted to move all the upper and all the lower chisels convergently with a slab positioned therebetween, means adapted to energize and deenergize said hydraulic power means, a chisel setting mechanism for movingeach of said chisels in firm engagement against both surfaces of the slab, and a trigger mechanism connected with said means to deenergize said hydraulic power means and responsive to the chisel first contacting the surface of said slab whereby to automatically set all the chisel cutting heads against the slab prior to applying additional cutting pressure thereon.

Riddle Apr. 7, 1942 Graham et a1 May 15, 1951 Jenkins et a1 Oct. 30, 1956 

